This patch adds basic support for the AMCC 460EX/460GT PPC's.

Signed-off-by: Stefan Roese <sr@denx.de>

Signed-off-by: Stefan Roese <sr@denx.de>

- Add support for PPC440EPx & PPC440GRx
- Add support for PPC440EP(x)/GR(x) NAND controller
  in cpu/ppc4xx directory
- Add NAND boot functionality for Sequoia board,
  please see doc/README.nand-boot-ppc440 for details
- This Sequoia NAND image doesn't support environment
  in NAND for now. This will be added in a short while.
Patch by Stefan Roese, 07 Sep 2006

Add support for IBM PPC440GX. Multiple EMAC Ethernet devices,
select MDI port based on enabled EMAC device.
Add support for XES Inc <http://www.xes-inc.com> XPedite1000 440GX
base PrPMC board.

  - remove trailing white space, trailing empty lines, C++ comments, etc.
  - split cmd_boot.c (separate cmd_bdinfo.c and cmd_load.c)

* Patches by Kenneth Johansson, 25 Jun 2003:
  - major rework of command structure
    (work done mostly by Michal Cendrowski and Joakim Kristiansen)